1. Field of the Invention
Embodiments of the present invention generally relate to a pad conditioning module and disk for conditioning chemical mechanical polishing pads.
2. Description of the Related Art
Chemical mechanical polishing (CMP) is used to smooth the surface topography of a substrate in the manufacture of integrated circuits, displays, photovoltaic devices, and the like. CMP removes materials from the substrate surface in part by chemical dissolution, while concurrently mechanically polishing the substrate. Chemical dissolution is performed by applying reactive chemical slurry to the substrate surface to remove materials from the substrate surface. The slurry is applied to the substrate surface by contact with a polishing pad disposed on a platen. A mechanical component of the polishing process is performed by providing relative motion between the substrate, the polishing pad, and the slurry therebetween.
After polishing a number of substrates, the polishing pad degrades and/or becomes “glazed” and is unable to consistently provide a desired polishing uniformity and rate. Glazing occurs when the polishing pad becomes excessively worn. The peaks of the polishing pad are pressed down and the pits of the polishing pad are filled with particulates, resulting in a smoother, less abrasive polishing surface.
To remedy polishing pad glazing, the pad is periodically conditioned by a pad conditioning disk having a conditioning face with abrasive particles, such as diamond particles, which is pressed against the used polishing surface of the polishing pad. The pad conditioning disk is typically mounted on an arm that oscillates while the conditioning disk is rotated and pressed against the polishing surface of the polishing pad.
However, often times, the surface of a conventional pad conditioning disk becomes pitted or eroded as a result of repetitive conditioning of the polishing surface of the polishing pad due to uneven contact with the surface of the polishing pad.
Therefore, an improved conditioning disk is needed that is capable of providing improved pressure distribution to the polishing surface of a polishing pad during conditioning of the polishing pad.